class Animal:
    name='animal'
    def shout(self):
        print('animal shout')
animal=Animal()
print(animal.name)
animal.shout()

class Dog:
    name='dog'
    def __init__(self):
       self.age=10
    def eat(self):
        print('dog eat')
dog=Dog()
print(dog.name)
dog.eat()

dog1=Dog()
print(dog1.name)
print(Dog.name)

dog1.name="wwwww"

print(dog1.name)
print(Dog.name)

Dog.name="ddddd"
print(dog1.name)
print(Dog.name)
dog2=Dog()
print(dog2.name)
# 类属性只能类对象来改